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This article belongs to the Special Issue Pre-breeding towards the Effective Utilization of Plant Genetic Resources., Durum wheat landraces have a high potential for breeding but they remain underexploited due to several factors, including the insufficient evaluation of these plant materials and the lack of efficient selection tools for transferring target traits into elite backgrounds. In this work, we characterized 150 accessions of the Spanish durum wheat collection for stem cross section, height and heading date. Continuous variation and high heritabilities were recorded for the stem area, pith area, pith diameter, culm wall thickness, height and heading date. The accessions were genotyped with DArTSeq markers, which were aligned to the durum wheat ‘Svevo’ genome. The markers corresponding to genes, with a minor allele frequency above 5% and less than 10% of missing data, were used for genome-wide association scan analysis. Twenty-nine marker-trait associations (MTAs) were identified and compared with the positions of previously known QTLs. MTAs for height and heading date co-localized with the QTLs for these traits. In addition, all the MTAs for stem traits in chromosome 2B were located in the corresponding synteny regions of the markers associated with lodging in bread wheat. Finally, several MTAs for stem traits co-located with the QTL for wheat stem sawfly (WSS) resistance. The results presented herein reveal the same genomic regions in chromosome 2B are involved in the genetic control of stem traits and lodging tolerance in both durum and bread wheat. In addition, these results suggest the importance of stem traits for WSS resistance and the potential of these landraces as donors for lodging tolerance and WSS resistance enhancement. In this context, the MTAs for stem-related traits identified in this work can serve as a reference for further development of markers for the introgression of target traits into elite material., This research was funded by the Instituto de Investigación y Formación Agraria y Pesquera (IFAPA), Junta de Andalucía, grant number AVA-AVA2019.020 cofounded at 80% by FEDER. C.M.A., J.S. and S.G.A. are members of the FiRCMe Network, funded by Ministerio de Economía, Industria y Competitividad (AGL2016-81855-REDT). M.D.R.-R. was the recipient of a fellowship from the Ministerio de Ciencia, Innovación y Universidades (PRE2018-084037).

The UK’s National Institute for Health and Care Excellence (NICE) Preterm labour and birth guideline recommends use of magnesium sulphate (MgSO4) in deliveries below 30 weeks’ gestation to prevent cerebral palsy and other neurological problems associated with preterm delivery. Despite national guidance, the uptake of MgSO4 administration in eligible women has been slow. NHS England has rolled out the PReCePT Quality Improvement (QI) toolkit to increase uptake of MgSO4 in preterm deliveries. The toolkit is designed to increase maternity staff knowledge about MgSO4 and provides training and practical tools to help staff consider use in eligible women. The PReCePT trial will evaluate the effectiveness of an enhanced support model of implementing the QI toolkit, compared with the standard support model. The standard support arm (control) receives the QI toolkit and regional-level support for a midwife/obstetric ‘champion’. The enhanced support arm (intervention) receives this plus additional clinical backfill funding and unit-level QI micro-coaching.This is a cluster randomised controlled trial designed to include 48 maternity units randomised (2:1 ratio) to standard or enhanced support. Units are eligible for inclusion if they have ten or more pre-term (< 30 weeks’ gestation) deliveries annually and MgSO4 uptake of 70% or less. Randomisation is stratified by previous level of MgSO4 uptake. The QI intervention is implemented over nine months. All units are followed up for a further nine months. Blinding is not possible due to the nature of the intervention.The primary outcome is the proportion of MgSO4 uptake amongst eligible women at follow-up, adjusting for uptake before implementation of the toolkit. The effectiveness of the intervention will be assessed using weighted linear regression on data from the National Neonatal Research Database. Semi-structured qualitative staff interviews will inform understanding of the process and outcomes. Economic evaluation will describe total costs and cost-effectiveness.STRENGTHS AND LIMITATIONSStrengthsThe first randomised controlled trial comparing two models of supporting the implementation of a Quality Improvement toolkit in perinatal medicine.A comprehensive evaluation, involving quantitative, qualitative and process measures including costs, to assess impact of the toolkit on the uptake of magnesium sulphate and team working.The National Neonatal Audit Programme (NNAP) and National Neonatal Registry Database (NNRD) provides robust routine data collection infrastructure for the primary outcome, also allowing future assessment of sustainability within participating units as well as uptake across the country.LimitationsThis pragmatic trial will reflect the conduct of scaling up a local initiative to a national level, where adherence to trial timelines may vary due to differences in local settings, procedures for permissions/approvals, and team capacity.Communication about the trial through formal and informal media channels may raise general awareness and thus improve background uptake nationally. Such contamination across trial groups may require assessment and adjustment in sensitivity analyses.

Nanotechnology is emerging as a very promising tool towards more efficient and sustainable practices in agriculture. In this work, we propose the use of non-toxic calcium phosphate nanoparticles doped with urea (U-ACP) for the fertilization of Triticum durum plants. U-ACP nanoparticles present very similar morphology, structure, and composition than the amorphous precursor of bone mineral, but contain a considerable amount of nitrogen as adsorbed urea (up to ca. 6 wt % urea). Tests on Triticum durum plants indicated that yields and quality of the crops treated with the nanoparticles at reduced nitrogen dosages (by 40%) were unaltered in comparison to positive control plants, which were given the minimum N dosages to obtain the highest values of yield and quality in fields. In addition, optical microscopy inspections showed that Alizarin Red S stained nanoparticles were able to penetrate through the epidermis of the roots or the stomata of the leaves. We observed that the uptake through the roots occurs much faster than through the leaves (1 h vs. 2 days, respectively). Our results highlight the potential of engineering nanoparticles to provide a considerable efficiency of nitrogen uptake by durum wheat and open the door to design more sustainable practices for the fertilization of wheat in fields., This research was funded by Fondazione CARIPLO (project no. 2016-0648: Romancing the stone: size-controlled HYdroxyaPATItes for sustainable Agriculture–HYPATIA) and the Spanish Ministerio de Ciencia, Innovación y Universidades (MCIU/AEI/FEDER) with the Projects NanoSmart (RYC-2016-21042) and NanoVIT (RTI-2018-095794-A-C22). GBRR also acknowledges the Spanish MICINN for her postdoctoral contract within the Juan de la Cierva Program (JdC-2017).

Oat crop is not particularly well adapted to hot and dry weather, as shown by a 3-fold yield reduction in Mediterranean compared to Northern regions. As a consequence, there is a need to identify more resilient oats adapted to current Mediterranean and future climate conditions. Here, we studied the performance of oat landraces under Mediterranean conditions, including the resistance to their most devastating disease, the crown rust. One hundred forty-one genetically characterized Spanish landraces were evaluated over two crop seasons at four contrasting locations in Spain and Egypt. Genotype-environment interactions were studied using heritability-adjusted genotype plus genotype-environment biplot analyses. The impact of climate variables on agronomic traits and the adaptation of particular landraces to environmental factors were inferred from non-metric multivariate scaling and canonical correspondence analyses. Results show an average oat landrace grain yield of 1500 kg/ha, which is similar to the mean yield of commercial varieties. Nonetheless, commercial varieties had 20% higher harvest index than landraces, which is explained by the higher biomass of landraces. Moreover, oat landraces showed high levels of rust resistance with mean values of the area under the disease curve of 2.58, which is approximately 25% lower than that of commercial varieties. Furthermore, several landraces carried a broad spectrum type of resistance which is expected to be more durable and efficient against different rust isolates., This work was supported by the Spanish Ministry of Economy and Competitiveness [AGL2013-48687AGR] and regional government through the AGR-253 group, as well as the European Regional and Social Development Funds and Egyptian Academy of Scientific Research and Technology—ASRT through AECID program. JSM is holder of an FPU fellowship from the Spanish Ministry of Science and Innovation. NR is holder of a Ramón y Cajal Post-doctoral fellowship from the Spanish Ministry of Economy and competitiveness (MINECO).

A germplasm collection of 484 accessions of Vicia faba was screened for resistance to rust (Uromyces viciae-fabae) under field conditions. Accessions varied in the levels of rust infection, although no complete resistance was identified. Stability of resistance of the 39 most-resistant accessions was tested in a multi-location experiment in Austria, Egypt, Tunisia, United Kingdom and Spain over three additional field seasons. Genotype × environment interaction accounted for 43% of the sum of squares of the multi-environment evaluation, revealing instability of the phenotypic expression across environments. This might hamper the efficiency of selection suggesting the need for selection in different environments. Three possible mega-environments were discerned in the studied area, Mediterranean (Spain, Tunisia and Egypt), Oceanic (UK) and Continental (Austria). Córdoba (Spain) and Kafr El-Sheik (Egypt) showed as ideal environments for rust resistance screenings within Mediterranean environment. Several accessions (300, 303, 311, 313, 720, 1196 and 1271) were grouped as moderately to highly resistant in the three defined mega-environments. These accessions showed clear differences both in terms of reduced disease severity and high stability, which make them good candidates for international faba bean breeding programmes. Concerning each mega-environment, accessions 300 and 311 were the most resistant and stable ones across the Mediterranean one, followed by accessions 720, 1022, 1272, 1320 and BPL261. On the contrary other accessions (313, 452, 481 and 1196) were the most resistant in Oceanic and Continental environments. However, 452 and 481 were susceptible in the Mediterranean mega-environment. This contrasting performance across the environments was also supported by contradictory performance of the checks BPL261 and Baraca in Oceanic and Continental environments, suggesting differential virulence in rust populations, which deserves further attention.

Leaf rust, caused by the fungus Puccinia triticina, is considered one of the most important foliar diseases in durum wheat. Hypersensitive resistance (HR) may be rapidly overcome by the pathogen when resistant cultivars are grown on a large acreage or following changes in virulence in the pathogen population. Prolonging the durability of the resistance requires uses of other types of resistance such as partial resistance (PR). In this study, six durum wheat lines provided by the International Center for Corn and Wheat Improvement (CIMMYT) with a high level of PR to leaf rust were studied in monocyclic tests in a growth chamber. Inoculations were performed on both primary and fifth leaves using the Spanish race DGB/BN. UV fluorescence microscopy was employed to determine microscopic components of the resistance, such as the number of early aborted infection units not associated with plant cell necrosis (EA−) and relative colony size (RCS) of the established infection units. Macroscopic components of PR such as latency period, infection frequency and uredinium size were measured as well. All six resistant lines were characterized by a higher EA− and smaller RCS respect to the susceptible control ‘Don Rafael’. Line 3 showed the highest level of PR. It had 22% of EA− compared with 4% in the susceptible control, and the smallest RCS (17% respect to RCS of ‘Don Rafael’) at adult plant stage. Both EA− and RCS had a high heritability (more than 97%) and the correlation with macroscopic parameters (latency period and uredinium size) was also high (significant at 0.001 level). Hence, PR to leaf rust in these durum wheat genotypes has been revealed at microscopic level (higher EA− and smaller RCS).

Lentil (Lens culinaris Medik.) is an important cool-season legume that can be severely damaged by rust (Uromyces viciae-fabae (Pers.) Schrot.) in many parts of the world. In this work, a collection of L. culinaris germplasm accessions was screened under growth chamber conditions for response to U. viciae-fabae. Several sources of incomplete resistance have been identified, both of hypersensitive and of non-hypersensitive nature. Incomplete hypersensitive resistance was due to a late-acting host cell necrosis that resulted in an intermediate infection type (IT). Incomplete non-hypersensitive resistance was due to a hampered cell penetration not associated with host cell necrosis, reducing the number of haustoria per colony and therefore hindering the growth of the colony and reducing and retarding disease development in spite of a high IT.

Faba bean (Vicia faba) production in Mediterranean and Near East agriculture is severely constrained by broomrape infection. The most widely distributed broomrape species affecting faba bean is Orobanche crenata, although O. foetida and Phelipanche aegyptiaca are of local importance. Only moderately resistant cultivars are available to farmers. Rizotrons studies allowed the dissection of resistance components in faba bean accessions against the very infective species O. crenata, O. foetida var. broteri and P. aegyptiaca, and to the inappropriate P. ramosa and O. foetida var. foetida. Results confirm that some levels of incomplete resistance are available, resulting in a reduced number of broomrape tubercles successfully formed per faba bean plant. Interestingly, the intermediate levels of resistance of cv. Baraca were operative against all broomrape populations and species studied, confirming previous reports on the stability of resistance of Baraca in field trials in different countries. Low induction of seed germination played a major role in the resistance against the inappropriate O. foetida var. foetida but not against the also inappropriate P. ramosa, neither to the infective species O. crenata, O. foetida var. broteri, or P. aegyptiaca. Negative tropism of germinated seeds with radicles growing away from faba bean roots was marked for both inappropriate species but was not observed in any of the infective species. Also, a proportion of radicles that had successfully contacted faba bean roots became necrotic, failing in starting tubercle development, particularly frequent for the two inappropriate species. Such necrosis was significant also on radicles contacting resistant faba bean accessions, being particularly relevant for Spanish O. crenata population, and lower although still significant in some accessions against Syrian O. crenata and P. aegyptiaca, suggesting that this might also be an operative mechanism to be selected and further exploited in faba bean resistance breeding. Even formed broomrape tubercles might later become necrotic, particularly in the case of some of the resistant faba bean accessions to the Spanish O. crenata and to P. aegyptiaca but not to the very infective Syrian O. crenata or O. foetida var. broteri., Authors are greatly indebted to European Union projects FP7-ARIMNet-Medileg and FP7-LEGATO (grant agreement 613551) for financial support.

Rust is a serious disease of pea whose casual agent is not always understood. In this paper we studied reaction of pea accessions to seven rust species infecting closely related legumes, finding that indeed pea can be infected mainly by . Uromyces pisi, followed by . Uromyces viciae-fabae. Other rust species like . Uromyces striatus, . Uromyces ciceris-arietini, . Uromyces anthyllidis and . Uromyces vignae can also infect and reproduce on pea, although in a minor extent. All . U. pisi isolates tested were very virulent on pea accessions, but isolates UpPt-03 and UpKeS-05 (from Palmar de Troya, Spain and Kafr-El-Sheik, Egypt respectively) were significantly most infective. In addition to this we studied in detail the host range of . U. pisi by inoculating multiple accessions of various legumes with urediospores of seven isolates of . U. pisi from different geographical origins. Both experiments were performed under controlled conditions. Based on the evidence presented here the host range of . U. pisi is greater than previously recorded, including genotypes belonging to . Cicer arietinum, . Vicia articulada, . Vicia ervilia and . Vicia faba, which were not mentioned before. © 2012 Elsevier Ltd., Financial support by the Spanish ProjectsAGL2008-01239 and P07-AGR02883 is acknowledged.

The authors acknowledge the Spanish Project RTA-2009-00061-C03, from INIA, for the financial support.

This study evaluates the changes caused by breeding in the genotype × environment interaction of the bread wheat varieties most widely cultivated in Spain during the 20th century. A set of 27 varieties was tested in 8 environments representative of the bread wheat growing areas in the country. Minimum temperature and thermal time from sowing to heading were the main environmental traits determining genotype × environment (GE) interactions for yield. Landraces were the least productive and showed specific adaptation to environments with low minimum temperatures before heading and high relative air humidity after heading. Yield consistency was low in landraces due to large environmental effects on the number of spikes and grain weight. Old-bred varieties (released between 1945 and 1955) were the first step towards breeding for wide adaptation due to the lower dependence of their final spike number and grain weight on water availability during grain filling. Differences in the adaptation pattern of the varieties introduced since the 1960s were caused by their growth habit. Winter types were more widely adapted than spring ones, mostly because they had a more consistent number of grains per spike. Grain weight of winter varieties was enhanced in environments with high relative humidity during grain filling. Spring varieties had more grains per spike in environments with high minimum temperatures and thermal time before heading. The number of grains per spike was the yield component that most closely followed the pattern of adaptation observed for grain yield.

Chocolate spot is an important disease of faba bean (Vicia faba) caused by the necrotrophic fungus Botrytis fabae. The aims of this work were: i) to compare different methods of screening for resistance; ii) to assess the influence of the age of host tissue and temperature on this pathosystem. To this effect, a collection of 42 faba bean accessions was evaluated in mature plant stage in the field in Cordoba (Southern Spain) and in detached leaflet and whole plant tests under controlled conditions. Field results correlated better with those of the whole plant test than with those of the detached leaflet assay. Integration of results from the field and whole plant experiments resulted in the selection of six accessions of interest as sources of resistance. Influence of leaf age on disease development was found to be genotype dependent. Older leaves were more susceptible than younger ones in 23 accessions, while no difference between leaf ages was detected in the remaining accessions. The effects of plant age and temperature were assessed by a whole plant test on seven accessions at two plant ages (4 and 7 weeks) and three temperatures (13, 20, and 25°C). Results showed that the differential genotypic responses to B. fabae were not significantly influenced by either plant age or temperature, although there was a tendency towards lower susceptibility to chocolate spot in faba bean plants as they become older. Further, a partial high-temperature, young-plant resistance was detected. © 2011 KNPV., Financial support by Spanish project AGL2008-01239 is acknowledged.

The aim of this work was to identify Vicia faba germplasm resistant both to rust and chocolate spot. A collection of 43 accessions of V. faba previously identified as chocolate-spot resistant was evaluated for rust and chocolate spot resistance in Egypt and in Spain. The genotype and genotype × environment (GGE) biplot analyses allowed the selection of 11 accessions resistant to both diseases in those locations. These 11 accessions were evaluated for rust in an additional field trial in Spain, all performing better than the susceptible check. The joint analysis of the 11 accessions in the four field trials where they had been evaluated revealed no significant effects either for genotype, environment or the genotype × environment interaction. They are hence promising sources of resistance, both for their low severities and their stable responses across the studied environments. This collection was also tested under controlled conditions against the Egyptian and the Spanish isolates of rust present in the field trials further underlining the stable performance of these genotypes. Finally, the effect of previous infection with chocolate spot on rust resistance was assessed under controlled conditions and no influence of it was found. © 2011 Elsevier B.V.

An isolate of Puccinia coronata f.sp. avenae with virulence against the oat crown rust resistance gene Pc94 was discovered in oat fields in Cordoba, Spain. In order to identify alternative sources of resistance to this virulent isolate, a collection of 159 Avena accessions, including 107 A. sativa and 29 A. byzantina landraces and 23 commercial A. sativa and A. strigosa cultivars, was screened. Eight resistant landraces and four cultivars were selected according to macroscopic assessment to further characterize the operative defence mechanisms. Histological studies showed a range of defence mechanisms, acting alone or in combination, which impeded fungal development at different stages. Some accessions allowed reduced fungal growth before mesophyll penetration. In others, the fungus was arrested at the penetration stage by mesophyll cell wall strengthening and/or papilla deposition. Mesophyll cells of several accessions were penetrated by the fungus, but then the hypersensitive response (HR) leading to cell death hampered fungal development. In some cases cell death was very fast and colonies aborted early, whereas in other cases necrosis was observed later and associated with numerous secondary hyphae, suggesting a slow HR. Characterization of defence mechanisms will be useful for breeding programmes and for further cellular and molecular studies to unravel the bases of resistance. Commonalities with the resistance of the same oat collection to powdery mildew are discussed.

The effectiveness of eleven foliar-applied fungicides on faba bean rust (Uromyces viciae-fabae (Pers.) J. Schröt.) and on the seed yield of faba bean (Vicia faba L.) were studied in growth chambers and in the field in Spain. Fungicides were tested at recommended and reduced rates. All the fungicides tested provided very effective preventive control in the growth chamber studies. Triazoles (difenoconazol, epoxiconazol, tebuconazol) and their mixtures with benzimidazoles (carbendazim-flutriafol and carbendazim-flusilazole) provided the most effective curative effect, even at 25% of recommended concentrations. They were followed by dithiocarbamates, copper dithiocarbamate mixture, carboxamide and chlorothalonil. Triazoles, benzimidazole-triazole mixtures and carboxamide maintained their effect until 15 days after fungicide application.Under field conditions, rust infection caused 22-26% yield reduction. All fungicides except mancozeb caused a significant decrease in disease severity under field conditions, but only treatments with triazoles and benzimidazole-triazole mixtures provided significant yield increases (22.7-15.6%) when applied twice. Three applications of oxycarbosin or copper-mancozeb were needed to provide a significant yield increase. Dithiocarbamates (thiram, maneb or mancozeb) or chlorothalonil reduced rust severity but did not provide a significant yield increase. © 2011 Elsevier Ltd., Financial support by Spanish projectsAGL2008-01239 and AECID-D/026716/09 is acknowledged.

DNA sequence analysis of the nuclear ribosomal internal transcribed spacer region (ITS) was performed to determine phylogenetic relationship between 49 isolates of rusts infecting grain and forage legumes. Isolates were collected from different hosts and distinct geographic origins and represent eight species of Uromyces: U. anthyllidis, U. appendiculatus, U. ciceris-arietini, U. minor, U. pisi, U. striatus, U. viciae-fabae and U. vignae. ITS sequences revealed length polymorphisms and variation in DNA sequence that were used to characterize phylogenetic relationships by maximum parsimony, maximum likelihood and Bayesian analyses which in general agreed revealing the presence of four clearly distinct clades. Clade one included the isolates causing rust on chickpea, fenugreek and alfalfa. Clade two was composed by rust isolates of field clover and pea plants, while the third clade was formed by bean and cowpea isolates. Clade four was the largest and included all the rust isolates infecting faba bean. Within this clade, the highly supported subclusters of U. viciae-fabae collected on Lens culinaris, U. viciae-fabae collected on Vicia sativa and U. viciae-fabae collected on Lathyrus palustris suggest an ongoing process of host specialization.

The authors are greatly indebted to the Spanish projects AGL2008-01239/AGR and P07-AGR-02883 for financial support.

Pea is an important grain legume mainly grown as spring crop in temperate regions. However, in areas with mild winters and dry springs, like Mediterranean type environments, spring pea types are autumn sown. Unfortunately, little efforts have been made so far in pea breeding for constraints typical of these environments, such as crenate broomrape (Orobanche crenata), rust (Uromyces pisi), powdery mildew (Erysiphe pisi) and ascochyta blight ( Mycosphaerella pinodes ). In this paper we revise the present state of the art in pea breeding against these diseases and we will critically discuss present progress and future perspectives.

A germplasm collection of 2759 pea accessions was screened for resistance against Uromyces pisi (Pers.) Wint. All accessions displayed a compatible interaction (high infection type) both in adult plants under field conditions and in seedlings under growth chamber conditions, but with varying levels of disease reduction. The identified resistance was based on reduction of disease severity with no associated host cell necrosis, which fits the definition of Partial Resistance. No complete resistance or incomplete resistance based on hypersensitivity was observed.

The aim of this work was to find new sources of resistance to chocolate spot disease, and to validate their stability across different environments. In order to do so, a collection of 307 accessions of Vicia faba was screened for resistance to Botrytis fabae under field conditions; stability of resistance of the 40 most-resistant accessions was tested in a multi-location experiment in Austria, Chile, Egypt, France and Spain over two field seasons. Although complete resistance was not found, nine accessions showed interesting levels of incomplete resistance (ranging from 10 to 20% of average severity across environments, maximum average severity being 47.9%). Genotype × environment interaction accounted for 22% of the sum of squares of the multi-environment evaluation, revealing instability of the phenotypic expression across environments. This usually hampers the efficiency of selection and reduces the adaptability of the plant material. Three accessions stand out for their consistent resistance, both in terms of reduced disease severity and high stability, which make them good candidates for breeding programs. As for environments, those with the highest total severity mean were the most discriminant between accessions. In contrast, those with lower severity means were the most representative of the whole range of environments. It can be concluded that validation of resistance to chocolate spot in different environments is an essential step when screening for material of interest and should be taken into account for further works.

Orobanche crenata, Orobanche aegyptiaca and Orobanche foetida constitute serious threats to grain legumes in the Mediterranean Basin. Lentil can be severely infected by O. crenata. It can also be damaged although with less virulence by O. aegyptiaca, and can only be slightly infected by O. foetida. Resistance breeding is hampered by scarcity of proper sources of resistance in cultivated lentil and of a reliable and practical screening procedure. A germplasm collection of 23 wild Lens spp. accessions was screened for resistance to O. crenata under field conditions. A wide range of responses was observed, from complete resistance to susceptibility. The higher levels of resistance were observed in accessions of Lens ervoides, Lens odemensis and Lens orientalis. Resistance of selected accessions proved to be mainly because of early hampered tubercle formation, with no observed necrosis of established tubercles. No differences were observed in levels of induction of broomrape germination, but necrosis of broomrape radicles was significant in some cases, particularly in the L. odemensis― O. foetida interaction. Escape because of the reduced root biomass diminishing the chance of contact between host and parasite was also observed in L. odemensis.

The Italian durum wheat cultivar Creso possesses a high level of durable resistance to leaf rust based on both hypersensitive and non-hypersensitive components. In order to investigate the genetic basis of this resistance, a segregating population composed of 123 recombinant inbred lines (RILs) derived from the cross Creso × Pedroso, was evaluated for disease severity in adult plants under field conditions. Furthermore, the resistance of parents and RILs was evaluated by assessing macroscopically the latency period and microscopically the number and type of pathogen colonies formed following artificial inoculation with a specific isolate. This experiment was performed at controlled conditions at two developmental stages. Besides some minor QTLs, one major QTL explaining both reduction of disease severity in the field and increased latency period was found on the long arm of chromosome 7B, and closely associated PCR-based and DArT markers were identified.

Common vetch ( Vicia sativa ) is widely used as green manure, pasture, silage, hay and for grain for livestock feed. Its major areas of cultivation coincide with areas of heavy infestation by broomrapes, mainly Orobanche crenata , but also Orobanche aegyptiaca and Orobanche foetida . We report resistance against O. crenata in V. sativa observed in the field, and characterised for selected resistant accessions both in pots and mini-rhizotrons against several Orobanche species. All species studied formed tubercles on common vetch although in varying densities depending on the species and the accessions. However a significant proportion of these became necrotic and died, with frequencies varying with Orobanche species and V. sativa accessions. The cultivar Mezquita is more resistant than PI-183723 against the two populations of O. crenata studied, and also against O. aegyptiaca . However the mechanistic basis of the resistance of Mezquita seems to differ with the Orobanche species. Its resistance against O. crenata is based on retarded development of established tubercles, whereas resistance against O. aegyptiaca is active earlier reducing tubercle formation.

Genetic variation of 30 different Uromyces isolates collected on faba bean, lentil, common vetch, pea, chickpea, alfalfa, cowpea and lupin was studied. Random Amplified Polymorphic DNA markers were used showing clear differences among Uromyces species. Uromyces viciae-fabae isolates clustered according to the host, with a clear cluster including all U. viciae-fabae ex Vicia faba isolates. The U. viciae-fabae ex Lens culinaris isolate was the nearest to the cluster of U. viciae faba ex V. faba isolates, followed by U. pisi from Canada and U. viciae-fabae ex V. sativa. No association was found among molecular diversity and virulence or geographic origin within U. vicia-fabae ex V. faba isolates. Among the three U. pisi isolates considered, a great variability was observed and no grouping could be established. The most different isolate from the rest of species considered was U. striatus, followed by U. vignae. The two U. ciceris-arietini isolates clustered together and so did the two U. lupinicolus isolates., Financial support by the European Union project QLK5-CT2002-02307 and by the Spanish project AGL2005-01781 is acknowledged.

The weedy root parasite Orobanche crenata constitutes a serious threat to lentils and other legumes grown in the Mediterranean and western Asia. Control strategies have centred on agronomic practices and the use of herbicides. Resistance breeding is hampered by scarcity of proper sources of resistance and of a reliable and practical screening procedure. A stepwise procedure was used here. A Spanish germplasm collection of 234 accessions of lentils (Lens culinaris) was screened for resistance to crenate broomrape under field conditions. A wide range of responses was observed, however, complete resistance was not detected. Some accessions exhibited a substantial reduction in broomrape infection. Thirty-five lentil accessions with reduced broomrape infection were selected for further screening in the field and to determine the components of resistance in pot and in mini-rhizotron experiments. Low infection seemed to be based on a combination of various escape and resistance mechanisms: (i) a lower root density, (ii) a lower induction of Orobanche seed germination, (iii) the reduced establishment of broomrape radicles and (iv) a limited development of established tubercles. In addition, necrosis of tubercles was observed in some accessions. This study shows how complementary in vitro screening methods may be used to rank and identify lentil accessions with potential broomrape resistance, based on different resistance mechanisms which may in the future be combined into a single cultivar by breeding.

Orobanche crenata is a weedy root parasite that causes huge damage to legume crops. Control strategies have centred around agronomic practices and the use of herbicides, although success has been marginal. Our field experiments show that O. crenata infection on faba bean and pea is reduced when these host crops are intercropped with oat. The number of O. crenata plants per host plant decreased as the proportion of oats increased in the intercrop. Pot and rhizotron experiments confirmed the reduction of infection in faba bean intercropped with cereals. It is suggested that inhibition of O. crenata seed germination by allelochemicals released by cereal roots is the mechanism for reduction of O. crenata infection.

A set of 23 recombinant lines (RLs) of barley (Hordeum vulgare L.) derived from H. vulgare × H. bulbosum L. crosses was inoculated with barley leaf rust (Puccinia hordei) and powdery mildew (Blumeria graminis f.sp. hordei) at the seedling stage to identify their levels and mechanisms of resistance. Eight RLs were studied further in glasshouse and field tests. All three barley parents (‘Emir’, ‘Golden Promise’ and ‘Vada’) were highly susceptible to powdery mildew and leaf rust isolates. Several RLs showed partial resistance expressed as high relative latency periods and low relative infection frequencies against leaf rust. This high level of partial resistance was due to a very high level of early aborting colonies without host cell necrosis. Several RLs showed hypersensitive resistance to some or all isolates. For powdery mildew, one RL was completely resistant to the CC1 isolate and had a hypersensitive resistance to the CO-02 isolate. Three RLs derived from ‘Emir’ were completely resistant to both powdery mildew isolates, and three more RLs tested in the field had higher levels of partial resistance than their parents. The results indicate that H. bulbosum contains major and minor gene(s) for resistance to leaf rust and powdery mildew that can be transferred to cultivated barley., The authors acknowledge the Spanish Agency for International Cooperation (AECI), CICYT projects AGF99-1036-CO1 and AGL2005-01781 for financial support in Spain. R. Pickering acknowledges the financial support of the Foundation for Research, Science and Technology (New Zealand).

SUMMARY Background Sustained virological response rates of up to 52% have been obtained with peginterferon α2a (40 kDa) plus ribavirin in patients suffering from chronic hepatitis C genotype 1 in randomized-controlled trials. Aim To assess early virological response and its clinical utility in predicting an sustained virological response in patients suffering from chronic hepatitis C genotype 1 in routine clinical practice in Spain. Methods Treatment-naive patients received pegylated interferon α2a (40 kDa) 180 µg/week plus ribavirin 1000/1200 mg/day for 48 weeks, and were followed for a further 24 weeks. Overall, 475 patients received at least one dose of medication and were included in the efficacy population. Results The overall sustained virological response rate was 48%. Of those with week 12 virological data, 83% had an early virological response. The negative predictive value of an early virological response was 93%. Conclusion If sustained virological response is the goal, a treatment-decision based on a 12-week evaluation during routine clinical practice is feasible.

A set of bread wheat and durum wheat cultivars adapted to Spanish conditions was tested for resistance against leaf rust caused by different pathotypes of Puccinia triticina in field trials and in growth chamber studies. Lower levels of resistance were found in durum wheat than in bread wheat. The most frequent Lr genes found in bread wheat were Lr1, Lr10, Lr13, Lr20, Lr26 and Lr28. In durum wheat, additional resistance genes that differed from the known Lr genes were identified. The level of partial resistance to leaf rust was in general low, although significant levels were identified in some bread wheat and durum wheat cultivars.

A number of parasitic plants have become weeds, posing severe constraints to major crops including grain legumes. Breeding for resistance is acknowledged as the major component of an integrated control strategy. However, resistance against most parasitic weeds is difficult to access, scarce, of complex nature and of low heritability, making breeding for resistance a difficult task. As an exception, resistance against Striga gesnerioides based on a single gene has been identified in cowpea and widely exploited in breeding. In other crops, only moderate to low levels of incomplete resistance of complex inheritance against Orobanche species has been identified. This has made selection more difficult and has slowed down the breeding process, but the quantitative resistance resulting from tedious selection procedures has resulted in the release of cultivars with useful levels of incomplete resistance. Resistance is a multicomponent event, being the result of a battery of escape factors or resistance mechanisms acting at different levels of the infection process. Understanding these will help to detect existing genetic diversity for mechanisms that hamper infection. The combination of different resistance mechanisms into a single cultivar will provide durable resistance in the field. This can be facilitated by the use of in vitro screening methods that allow highly heritable resistance components to be identified, together with adoption of marker-assisted selection techniques.

In this paper we review the existence of sources of resistance and the various available screening methods for resistance in grain legumes against the airborne pathogens powdery mildews, downy mildews and rusts. Available resistance against these pathogens is not abundant and is particularly in risk of erosion owing to the constant generation and introduction of new races of the pathogen. A continuous search for more resistance sources is therefore a priority in legume breeding and special emphasis should be paid to selection of resistance mechanisms that are likely to be durable and to implementation of strategies to prolong the durability of existing resistance.

International audience; Necrotrophic pathogens of the cool season food legumes (pea, lentil, chickpea, faba bean and lupin) cause wide spread disease and severe crop losses throughout the world. Environmental conditions play an important role in the development and spread of these diseases. Form of inoculum, inoculum concentration and physiological plant growth stage all affect the degree of infection and the amount of crop loss. Measures to control these diseases have relied on identification of resistant germplasm and development of resistant varieties through screening in the field and in controlled environments. Procedures for screening and scoring germplasm and breeding lines for resistance have lacked uniformity among the various programs worldwide. However, this review highlights the most consistent screening and scoring procedures that are simple to use and provide reliable results. Sources of resistance to the major necrotrophic fungi are summarized for each of the cool season food legumes. Marker-assisted selection is underway for Ascochyta blight of pea, lentil and chickpea, and Phomopsis blight of lupin. Other measures such as fungicidal control and cultural control are also reviewed. The emerging genomic information on the model legume, Medicago truncatula, which has various degrees of genetic synteny with the cool season food legumes, has promise for identification of closely linked markers for resistance genes and possibly for eventual map-based cloning of resistance genes. Durable resistance to the necrotrophic pathogens is a common goal of cool season food legume breeders

Orobanche crenata Forsk. is a major constraint for pea production in Mediterranean and East Asian countries. To solve the problem of the lack of resistance in pea cultivars, a screening for resistance was performed under field conditions in a germplasm collection of 575 accessions of Pisum sativum L. No complete resistance was found but varying levels of resistance were identified and confirmed in further field seasons and in pots experiments in the greenhouse. Resistance was quantitative resulting in a reduction in the number of emerged broomrapes per pea plant. Broomrape infection and expression of resistance proved to be highly influenced by environmental conditions. Resistance is the consequence of the combination of several resistance mechanisms preventing or hampering establishment of broomrape and/or development of established tubercles. Resistance identified could suffice to prevent broomrape damage in normal years, but might need to be implemented with other control measures in very conducive years. Resistant accessions have been crossed with pea cultivars and submitted to a breeding programme in which accumulation of levels of resistance to broomrape is a priority.

Wheat leaf rust (Puccinia triticina) is becoming a serious concern in Spanish wheat, especially on durum wheat where acreage has enormously increased. Host resistance is the preferred method of disease control, but the virulence spectrum of the leaf rust population in Spain is currently unknown. In order to deploy effective Lr genes, this study was conducted to characterize the virulence spectrum of leaf rust in Andalusia (Spain). Isolates were obtained from surveys of wheat fields across Andalusia from 1998 to 2000. From 56 isolates phenotyped, 35 pathotypes were identified. Virulence to Lr10, Lr11, Lr14a, Lr14b and Lr18 was high (>96%), while virulence to Lr9 and Lr24 were not found. None of the isolates collected from durum wheat were virulent to Lr1, Lr3, Lr3ka, Lr3bg, Lr15, Lr16 and Lr17, while many of the isolates collected on bread wheat showed virulence on these genes, indicating a certain specialization in the leaf rust infecting durum wheat. Population dynamics of current wheat leaf rust pathotypes in terms of mutation and migration are discussed.

Crenate broomrape is a parasitic weed that represents a major constraint for pulse and forage legume production in the Mediterranean and West Asia regions. Control strategies have centered around agronomic practices and the use of herbicides, although success has been marginal. Resistance breeding is hampered by scarcity of proper sources of resistance and of a reliable and practical screening procedure. A germ plasm collection of 208 accessions of vetch belonging to 42 Vicia spp. was screened for resistance to crenate broomrape under field conditions. High levels of resistance were found in several species. Resistance of selected accessions was confirmed by a low induction of broomrape seed germination in pot and in vitro experiments. This was followed by a scarce establishment of broomrape radicles in contact with host roots and a limited development of established tubercles. In addition, a hypersensitive-like necrosis occasionally was observed, but at low frequency.

Summary The effect of early and late sowing dates on the establishment of Orobanche crenata Forsk. (crenate broomrape) in resistant and susceptible cultivars of faba bean (Vicia faba L.) and vetch (Vicia sativa L.) were studied over four seasons in southern Spain. Differences in establishment, development and shoot emergence of the parasite were compared. With resistant faba bean and vetch cultivars, there was reduced attachment and shoot emergence of O. crenata with all sowing dates. Susceptible cultivars were more severely affected by the parasite with early sowing. Orobanche crenata development was also delayed in resistant cultivars. Crop yield, estimated by the number of pods per plant, decreased with late sowings. The combined use of resistant cultivars and early sowing is a useful tool as part of an integrated control strategy. Resistant cultivars allow early sowing (with low O. crenata attack), thus avoiding yield losses due to the short crop cycle with late sowing.

Summary Crenate broomrape (Orobanche crenata) is a major constraint for legume cultivation in Mediterranean agriculture. Field trials, pot and in vitro experiments demonstrated that resistance to O. crenata is present in chickpea and wild species of Cicer. The resistance is the result of the combination of several mechanisms, including low induction of parasite seed germination and in some accessions, either a darkening at the infection site on the host root that prevents establishment, or a reduced development of established parasite tubercles.